John Hutton, the Work and Pensions Secretary, said: "There are a small number of parents who seem to think that paying for their kids is something they can simply choose not to do.

"It isn't. And these new powers will mean that non-payment brings real and lasting penalties.

The CSA needs root and branch reform not a gimmicky re-branding exercise

David Laws, Liberal Democrats

"The new rules will be simpler and more transparent, making it harder to hide income and giving us the power to deduct money direct from bank accounts as well as from earnings."

C-MEC will also work with government bodies including the Inland Revenue and Customs and Excise to establish parents' income and set maintenance levels.

'Changes now'

The shadow minister for family welfare, Maria Miller, said the proposed changes would not come fully into effect until 2013, offering "little support for the 1.4m families who are already stuck on the current failing system".

"These families need to see positive changes to the system now, which is why we have proposed the fast tracking of changes to the assessment process as part of this bill," she said.

"We must ensure the government is not inadvertently creating CSA mark three."

She added the Conservatives would put forward constructive proposals "to help restore parents' faith in the system" after studying the bill's details.

David Laws, the Liberal Democrats' work and pensions spokesman, said it was a "disgrace" that the government had taken 10 years to reform the CSA and "unforgivable" that the reforms would not come fully into force for six years.

"The CSA needs root and branch reform not a gimmicky re-branding exercise.

"Naming and shaming and placing curfews on absent parents who fail to pay their child support may grab a few headlines but it will be little comfort to the families who are owed up to £3.5bn in child support back-payments," said Mr Laws.

He added: "The CSA needs immediate wholesale reform moving its collection functions to the Treasury who are far better placed to enforce deduction of earnings, and creating a transparent appeals mechanism."

We are going to have children at school who will be told by other children in the playground that they have seen their father on the website

Kim FellowesFamily lawyer

Family lawyer Kim Fellowes told BBC Radio 4's Today programme she had "grave concerns" about the plans.

She said naming and shaming was unlikely to make parents pay maintenance but the "real worry" was how it would affect children.

Ms Fellowes told the programme: "We are going to have children at school who will be told by other children in the playground that they have seen their father on the website.

"That raises considerable human rights issues. And how are these children going to be protected?"

The CSA already had "extensive powers" it was failing to use, including the power to sell people's homes, she added.

"Surely that is the biggest incentive for a parent to pay," Ms Fellowes told Today.

In the first round of naming and shaming, more than 100 parents are being targeted. Most will have been found guilty in open court this year of failing to provide information or providing false information.

The parent who looks after the children will be first asked to give their permission for their former partner to be named.

Anyone who has faced action in the family courts for non-compliance will not be included as legal restrictions prevent that from happening.